1. Field of the Invention
The present invention relates to mower-conditioners which are machines which both cut standing crop and then condition the cut crop before discharging the same to the ground.
In this specification "right-hand," "left-hand," "forward," and "rearward" references are determined by standing at the rear of the machines and facing in the direction of forward operative travel thereof. Also, in the following description it is to be understood that such terms as "forward," "left" and "upwardly" are words of convenience and are not to be construed as limiting terms.
Mower-conditioners according to the invention may comprise a reciprocating cutterbar. However, preferably the mower means will be of the type comprising at least a pair of rotatable cutter units mounted side-by-side and each supporting at least one cutter blade operable to cut the standing crop by impact as opposed to shearing, during forward movement of the mower-conditioner.
The rotatable cutter units may be of the type comprising a disc-like structure supporting at its outer periphery at least one cutter blade and being driven from below by drive means which are arranged inside a housing, the housing extending below the cutter units and in transverse direction over substantially the total width of the machine. However, the rotatable cutter units may also be of the so-called "drum" type comprising top driven drums supporting at their lower ends flanges each of which supports at least one cutter blade at its outer periphery.
2. Description of the Prior Art
Some mower-conditioners currently in use have either a disc-type or a drum-type cutter assembly in combination with a pair of transversely-extending cooperating conditioner rolls. In operation, the standing crop is cut by means of the cutter units and flung rearwardly into the intake nip between the conditioner rolls. The conditioner rolls are rotated in a manner to receive the cut crop at their forwardly facing intake nip and to pull the crop therebetween, thereby "conditioning" it by which is meant squeezing and cracking the stems so as to facilitate the evaporation of the moisture therefrom and hence speed up the drying cycle. Finally, the conditioner rolls eject the treated crop in a rearward direction depositing it in a windrow on the ground surface. In general, the operation of a mower-conditioner of the above type is satisfactory as far as mowing and conditioning are concerned.
However, the windrow formed by such a machine is often a rather thick and dense layer of crop, whereby the lowermost portions of the layer, in spite of the preceding conditioning operation, cannot dry quickly. For better and quicker drying, and thus to reap full benefit from the conditioning operation, the mown and conditioned crop should be further treated with a tedder or the like as soon as possible after the conditioning operation, so as to spread the crop in an even, thin and fluffy layer or windrow. The sun and wind can then easily and advantageously influence the drying speed of the mown crop. Since haymaking is often a "one person" operation, the subsequent treatment of the mown and conditioned crop is normally not started until the entire mowing and conditioning operation has been finished and hence the subsequent treatment is quite often delayed considerably, whereby the benefit of having conditioned the crop is at least partially annulled.
Moreover, it occasionally happens that the transitional movement of the crop from the cutter units to the conditioner rolls is not entirely satisfactory in as far as this movement is sometimes uneven. This ultimately results in the crop passing through the conditioner means in bunches, which again results in poor conditioning. The cause of this is considered to be that of the rolls not being sufficiently aggressive on the crop which is fed thereto.
In another known arrangement, a twin-rotor tedder has been hitched to the rear of a known four-disc rotary mower for spreading the crop immediately after being cut. In this arrangement the tedder extends parallel to the mower means at a considerable distance rearwardly thereof and has substantially the same width as the mower means. The axis of symmetry of both the mower means and the tedder coincide with each other. The tedder comprises a pair of supporting wheels arranged underneath respective rotor units, the latter each comprising four radially-outwardly projecting arms with generally upright tines at their outer ends. The lower ends of the tines, when in their forward position, extend to a location below and rearwardly of the rear edge of the associated mower means. The tedder units are rotated in opposite directions so as to have the tines moving towards each other at their forward ends.
In operation, the two machines are moved over the field, one behind the other. The standing crop is cut by the cutter units of the mower and is discharged thereby in a rearward direction at locations generally above and rearwardly of the areas between respective pairs of mower units. This means that the crop is discharged in two portions positioned generally forwardly of the rotary axis of the respective tedder rotors. This also means that, at the moment the tines contact the crop, the tines are moving in a direction generally transverse to the forward movement of the machine and hence generally perpendicular to the direction of movement of the crop being discharged from the mower cutter units. This, together with the fact that the tines extend in a generally upward direction, i.e. also generally perpendicular to the rearward direction of movement of the cut crop, results to some extent in the cut crop being thrown rearwardly between the tedder units in bunches rather than being evenly spread. The foregoing also results in a rather poor conditioning operation by the tedder, if any at all, as it is difficult for the tines to crack the crop stems when the crop is conveyed in bunches through the tedder means.
Also the relatively large distance between the mower means and the tedder may adversely influence the fluent transition of the crop from one to the other and hence also the spreading action of the tedder is adversely influenced. Moreover, because the equipment is merely two individual machines being towed one behind the other, the relative position of the two machines varies continuously due to ground irregularities. This again may adversely influence the transition of the crop from the mower means to the tedder.
Furthermore, the tines may occasionally touch the ground at the forward end of the tedder whereby soil may be mixed with the crop, on the one hand, and the tines may be submitted to heavy loads which may cause damage thereto, on the other hand.
Also because of the generally parallel relationship between the mower and tedder, normally the mown crop is spread (be it unevenly) over at least the full width of the mower. In other words, no strip of ground is left clear of mown crop for the right-hand tractor wheels to run therealong during the next run. Thus, after having spread the crop in a generally fluffy manner, a portion thereof will very soon be compressed again by the tractor wheels during the next run. More importantly, a considerable amount of cut crop is thrown on the still standing crop, which has to be cut during the next run. This is of course undesirable. Moreover, this occasionally may interfere with the proper cutting action of the machine during the next run.
In still another arrangement, rotary mower means, which are inclined relative to the transverse direction, have been combined with a single-rotor tedder extending horizontally and transversely. The tedder comprises a single transverse and horizontal shaft with a plurality of tines thereon and is arranged to rotate in such a manner as to operate on the cut crop either by a back-kicking action or an up-and-over action. The tedder is positioned at a considerable distance behind the mower means, whereby during operation, mown crop is first discharged onto the ground surface before being treated by the tedder. This has proven to be a considerable disadvantage for several reasons because the tedder has to lift mown crop from the ground, it may sometimes miss some of the crop and at other times may mix soil with the crop. Also, a tedder of this type has only a very minor conditioning action, if any at all. Furthermore, the spreading action, if any at all, is less than satisfactory.
In any event, some mower-conditioners known so far and which are generally satisfactory as far as mowing and conditioning are concerned, have no spreading action at all. Other machines with a certain spreading action are not adapted properly to condition the crop.
A mower-conditioner comprising rotary crop conditioner and spreader means mounted behind the mower means has been disclosed in U.S. Pat. No. 4,094,132. This combination is generally satisfactory as far as mowing, conditioning and spreading is concerned and, therefore, the machine disclosed in U.S. Pat. No. 4,094,132 is a very useful agricultural tool in many circumstances.
However, while the foregoing combination of three separate functions is very desirable for haymaking, there are certain circumstances when spreading is not desired. The foregoing machine therefore could not be used in such circumstances, unless special steps are taken. One such circumstance is when one wants to use the mower-conditioner for cutting grass prior to making silage. Grass is often merely cut and formed into a windrow where it stays about two days. Thereafter, the wilted grass is picked-up from the ground with the pick-up means of a forage harvester and chopped into silage.
The use of deflectors in mower-conditioners is already generally known in the art. However, all deflectors known until now are for further consolidating the windrow formed by the conditioning means. In one arrangement (German Utility Model No. 74.38.451), foldable deflector means are provided in combination with a mower-conditioner, wherein the conditioner means comprise a pair of transverse rolls. The deflector means, when in the operative position, further consolidate the shape of the windrow which is discharged from the conditioner means. The deflector means may flip upwardly for transport purposes.
In another arrangement (German Application No. 22.31.624), foldable deflector means with transversely-adjustable deflector baffles are provided in combination with a mower-conditioner having a twin roll transversely-extending conditioner means. The baffles are adjustable in a transverse direction so as to be able to change the width of the windrow at will. When the windrow discharged from the conditioner means is not to be further consolidated, then the deflector means may be swung upwardly and placed on top of the machine, out of the path of the cut crop.
Other adjustable baffles for mower-conditioners are known, for example from the U.S. Pat. Nos. 3,208,206 and 3,383,844. Again these baffles are used merely further to consolidate the windrow already formed by the machine.
Haymaking machinery such as rake tedders conventionally have one or more deflector means rearwardly of each pair of rotors. When the deflector means are in the operative position, a windrow is formed. When the deflector means are flipped upwardly out of the path of the cut crop, the rotors spread the crop evenly in a wide pattern over the field.